The present invention relates to a disposable diaper that can be easily put on a wearer in either case where the fastening tapes are fastened on the wearer's stomach side or where they are fastened on a wearer's back side, that can be easily put on whether the wearer is standing or lying, and that hardly impedes the wearer's movement while worn.
Known disposable diapers include fitted diapers having fastening tapes and pull-on diapers (also called pants type diapers or all-in-ones) that can be put on like ordinary underwear. Fitted disposable diapers are most commonly used in view of both their applicability to a full range of children, from newborns to toddlers, and because of their lower production cost.
A fitted disposable diaper is easy to put on a wearer such as a baby or an infant who is lying still on its back. However, it is not easy to put on an infant who is active enough to, for example, crawl about, being reluctant to wear a diaper, or have a new diaper put on.
Pull-on diapers are on the market for infants who can walk, but those suited for babies who have mastered crawling and are now on to pulling up themselves are not available yet. Even after a baby becomes able to pull itself up on something into a standing position, it is practically difficult to make the baby raise one foot to put on a pull-on diaper.
Hence, the present inventors have attempted to use a conventional fitted disposable diaper which is designed to be fastened on the stomach side in a back-to-front manner, that is, put on the diaper with its portion that is to be disposed on the wearer's back being applied to the stomach side. However, a conventional fitted disposable diaper is difficult to put on back to front, and, when fitted back to front, it is less capable of exhibiting its absorbing ability and more liable to leak while being worn.
JP-A-6-63077 proposes a diaper which is designed to be fastened with fastening tapes on the wearer's back side. The diaper has an elastic flap on each side of the stomach portion and a fastening tape fixed to each of the elastic flaps and enjoys ease of fastening on the wearer's back side as compared with traditional fitted disposable diapers. Nevertheless one often finds it convenient to fix fastening tapes on the wearer's front side. Therefore a diaper configured exclusively for fastening on the back side cannot avoid sacrificing ease to put on the front side, absorbing performance and leakproofness when used in an ordinary manner (i.e., fastened on the front side). The diaper of JP-A-6-63077 is designed for fastening only on the wearer's back side for application to infants who have developed to move actively and therefore gives no considerations to front side fastening usage.
JP-A-2-164363 proposes a diaper cover which is designed to be fastened with fastening tapes on the wearer's back side. WO95/12376 discloses a diaper having a pair of fastening ears which extend to the wearer's back side.
These proposed diaper cover and diaper are designed to be fastened on the back side and are therefore given no considerations to front side fastening usage.
Thus, a disposable diaper that sufficiently satisfies the ease of putting on as well as the absorption requirement when fastened on either side has not yet been proposed.